ABSTRACT
Background Oxidative damage may cause the functional dysfunction and death of retinal vascular endothelial cells(RVECs),and further leads to the development of retinal vascular diseases.Fufang xueshuantong has a therapeutic effect on retinal vascular diseases,but little is known about its molecular mechanism.Objective The goal of this study was to investigate the protective effects and mechanism of fufang xueshuantong on injury of human RVECs induced by tert-butyl hydroperoxide(t-BHP).Methods Human RVECs were isolated from healthy donor eyes and primarily cultured and then identified by flow cytometry.The third to fifth generations of cells were used in this experiments.The fufang xueshuantong solution of 0.0625,0.1250,0.2500,0.5000 and 1.0000 g/L were added in the cuhure plate with 5 × 104/L cells respectively in the experimental groups,and t-BHP of 75,100,200 and 300 μ.mol/L were added in the model control groups.MTT was used to detect the A490and survival rate of RVECs.The apoptotic rate and death rate of the cells were evaluated by double staining of Annexin V-FITC/PI.Morphology of human RVECs were examined using invert microscopy and Hoechst33258 staining.The expressions of nitro tyrosine (a marker of oxidative damage of protein)and 8-OHdG(a marker of oxidative damage of DNA)in human RVECs were assessed by the immunofluorescence staining.Western blot was used to detect the expressions of nuclear factorkappa B(NF-KB),p53,bcl-2 and bax after 6,12,24 hours t-BHP action.This study was approved by the Ethic Committee of Zhongshan Ophthalmic Center.Results No significant difference was found in A490value among the normal control group,0.0625,0.1250,0.2500,0.5000 and 1.0000 g/L fufang xueshuantong groups(F =1.989,P＞0.05).The survival rates of the cells were lower in 75,100,200 and 300 μmol/L t-BHP groups compared with corresponding fufang xueshuantong groups(t =14.57,13.82,21.51,32.64,P＜ 0.01).The percentages of normal cells were evidently lower in 75,100,200 and 300 μmol/L t-BHP compared with corresponding fufang xueshuantong groups(t=14.908,5.495,17.165,26.330,P＜0.01).The numbers of deformation and death of the human RVECs increased as the elevated concentration of t-BHP,but those in fufang xueshuantong groups were less than the t-BHP groups under the invert microscopy.Compared with t-BHP groups,the expressions of nitro tyrosine,8-OHdG,NF-KB,p53 and bax were lower but the expression of bcl-2 was higher in human RVECs with the statistically significant differences(P＜0.05).Fufang xueshuantong at the concentration of 0.2500 g/L showed maximally protective effect on human RVECs.Conclusions Fufang xueshuantong protects human RVECs against the t-BHP-induced injury through downregulating the expression of NF-kB,p53,bax and up-regulating the express of the bcl-2 protein.
ABSTRACT
<p><b>OBJECTIVE</b>To explore VEGF siRNA's effect on the immature fetal retinal microvascular endothelial cells in vitro.</p><p><b>METHOD</b>The fresh retinal micrangium was primarily cultured to obtain microvascular endothelial cells. CoCl2 was used to simulate oxygen-deficient conditions. siRNA directed against human VEGF was designed and chemically synthesized. There were 3 groups in our experiment: VEGF siRNA group, hypoxia control group, and negative siRNA control group. The fetal retinal micrangium vascular endothelial cells were transfected by using liposome. The expression levels of VEGF mRNA and protein were evaluated by RT-PCR and Western blotting 24, 48, 72 h after transfection, cell proliferation was evaluated by MTT method.</p><p><b>RESULT</b>The expression levels of VEGF mRNA decreased by 21.05%, 79.67%, and 90.48% 24 h, 48 h, and 72 h after transfection as compared to those in hypoxia control group, the expression level of VEGF protein had decreased by 14.58%, 66.97%, and 81.61% as compared to those in hypoxia control group. The siRNA could decrease cell proliferation under hypoxia too, the multiplication rate after 12, 24, 48, and 72 h decreased by 15.0%, 42.9%, 78.3% and 65.9%.</p><p><b>CONCLUSION</b>VEGF siRNA could down-regulate the expression of VEGF in immature fetal retinal microvascular endothelial cells and suppressed cell proliferation. Application of siRNA to inhibit expression of VEGF may be a hopeful way to prevent and cure ROP.</p>